﻿using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.Runtime.InteropServices;
using System.Text.RegularExpressions;
using System.Drawing;
using EasyHook;

namespace LunaInject
{
    public class Main : EasyHook.IEntryPoint
    {

        // Dictionary that matches a hdc handle for a poker table window to the value of its big blind
        static Dictionary<IntPtr, double> hdcList = new Dictionary<IntPtr, double>();
        IPokerBBMod.Program.IPokerModInterface Interface;
        LocalHook DrawTextExHook;

        Stack<String> Queue = new Stack<String>();

        // Regexes to match various poker client strings
        public static Regex money = new Regex(@"[\$\£\€](\d{1,3},)*\d+.?(\d{1,2}|)"); // Matches money eg $120.45
        public static Regex limit = new Regex(@"[\$\£\€](\d{1,3},)*\d+.?(\d{1,2}|)/[\$\£\€](\d{1,3},)*\d+.?(\d{1,2}|)"); // Matches a limit eg: $2/$4
        public static Regex bigBlind = new Regex(@"/[\$\£\€](\d{1,3},)*\d+.?(\d{1,2}|)"); // Matches the big blind in a limit.


        // DrawTextExW is the Win32 function that draw text to the graphical are of client and the function we need to intercept
        [DllImport("user32.dll", CharSet = CharSet.Unicode, SetLastError = true, CallingConvention = CallingConvention.StdCall)]
        static extern int DrawTextExW(IntPtr hdc, [In, Out, MarshalAs(UnmanagedType.LPTStr)] string lpString, int cchText, [In, Out, MarshalAs(UnmanagedType.Struct)] ref RECT lprc, uint dwDTFormat, [In, Out, MarshalAs(UnmanagedType.Struct)] ref DRAWTEXTPARAMS dparams);

        // Function to force a window to redraw
        [DllImport("user32.dll")]
        static extern bool InvalidateRect(IntPtr hWnd, IntPtr lpRect, bool bErase);

        [DllImport("gdi32.dll")]
        static extern uint SetTextColor(IntPtr hdc, int crColor);


        // Delegate that holds the definition of our callback function that will be called whenever we intercept the DrawTextExW function.
        [UnmanagedFunctionPointer(CallingConvention.StdCall, CharSet = CharSet.Unicode, SetLastError = true)]
        delegate int DDrawTextEx(IntPtr hdc, [In, Out, MarshalAs(UnmanagedType.LPTStr)] string lpString, int cchText, [In, Out, MarshalAs(UnmanagedType.Struct)] ref RECT lprc, uint dwDTFormat, [In, Out, MarshalAs(UnmanagedType.Struct)] ref DRAWTEXTPARAMS dparams);

        // Win32 Struct
        [Serializable, StructLayout(LayoutKind.Sequential)]
        public struct DRAWTEXTPARAMS
        {
            public uint cbSize;
            public int iTabLength;
            public int iLeftMargin;
            public int iRightMargin;
            public uint uiLengthDrawn;
        }

        // Win32 Struct
        [Serializable, StructLayout(LayoutKind.Sequential)]
        public struct RECT
        {
            public int Left;
            public int Top;
            public int Right;
            public int Bottom;

            public RECT(int left_, int top_, int right_, int bottom_)
            {
                Left = left_;
                Top = top_;
                Right = right_;
                Bottom = bottom_;
            }

            public int Height { get { return Bottom - Top; } }
            public int Width { get { return Right - Left; } }
        }


        public Main(RemoteHooking.IContext InContext, String InChannelName)
        {
            // connect to host...
            Interface = RemoteHooking.IpcConnectClient<IPokerBBMod.Program.IPokerModInterface>(InChannelName);
        }

        public void Run(RemoteHooking.IContext InContext, String InChannelName)
        {
            // Install system hook to detect calls to DrawTextExW that is made by the client and call the function DrawText_Hooked when ever this happens
            try
            {
                DrawTextExHook = LocalHook.Create(LocalHook.GetProcAddress("user32.dll", "DrawTextExW"), new DDrawTextEx(DrawText_Hooked), this);
                DrawTextExHook.ThreadACL.SetExclusiveACL(new Int32[] { 0 });
            }

            catch (Exception ExtInfo)
            {
                Interface.ReportException(ExtInfo);
                return;
            }

            //// force entire desktop to redraw to update IPoker graphics immediately 
            InvalidateRect((IntPtr)null, (IntPtr)null, true);

            RemoteHooking.WakeUpProcess();

            // wait for host process termination...
            try
            {
                while (true)
                {
                    Thread.Sleep(500);

                    // transmit newly monitored file accesses...
                    if (Queue.Count > 0)
                    {
                        String[] Package = null;

                        lock (Queue)
                        {
                            Package = Queue.ToArray();

                            Queue.Clear();
                        }

                    }
                    else
                        Interface.Ping();
                }
            }
            catch
            {
            }

            //// force entire desktop to redraw to update IPoker graphics immediately 
            InvalidateRect((IntPtr)null, (IntPtr)null, true);

        }

        // Intercept function that is called whenever the ipoker client draws text to its graphical area.
        // IPoker draws text in a convuluted way, and it is extremely difficult to tell which window a piece of text is being drawn on hence the messy workaround
        static int DrawText_Hooked(IntPtr hdc, [In, Out, MarshalAs(UnmanagedType.LPTStr)] string lpString, int cchText, [In, Out, MarshalAs(UnmanagedType.Struct)] ref RECT lprc, uint dwDTFormat, [In, Out, MarshalAs(UnmanagedType.Struct)] ref DRAWTEXTPARAMS dparams)
        {
            double bigBlindAmount;
            double m;

            // If detect a call to DrawTextEx with a new hdc and dwDTFormat 0x0800, check to see if the text being draw matches a limit regex (ie: it is a table title)
            // If so find the value of the big blind and add it to our dictionary of hdc/big blind pair values.
            if (dwDTFormat == 0x0800 && !hdcList.ContainsKey(hdc))
            {
                Match tableTitle = limit.Match(lpString);
                if (tableTitle.Success)
                {
                    double.TryParse(bigBlind.Match(tableTitle.Value).Value.Substring(2), out bigBlindAmount);

                    hdcList.Add(hdc, Convert.ToDouble(bigBlindAmount));
                    InvalidateRect((IntPtr)null, (IntPtr)null, true);
                }
            }

            // Match the string being drawn to a money regex, if it matches the client is trying to write text that is money values
            else if (money.IsMatch(lpString) && Double.TryParse(lpString.Substring(1), out m))
            {
                // Get the big blind value for the money value and convert to big blinds
                if (dwDTFormat == 0x0800 && hdcList.ContainsKey(hdc))
                {

                    bigBlindAmount = hdcList[hdc];
                    m = m / bigBlindAmount;

                    string stringOut = m.ToString("N") + " bb";

                    //if (colorStacks)
                    //{
                    //    SetTextColor(hdc, ColorTranslator.ToWin32(Color.Gold));
                    //}

                    // Pass this new value to the underlying Win32 system function to draw to the screen
                    return DrawTextExW(hdc, stringOut, -1, ref lprc, dwDTFormat, ref dparams);
                }

                // Work around to align text properly
                else
                {
                    return DrawTextExW(hdc, "", 8, ref lprc, dwDTFormat, ref dparams);
                }
            }

            // Otherwise just call the system DrawTextExW function with the original parameters without modification
            return DrawTextExW(hdc, lpString, cchText, ref lprc, dwDTFormat, ref dparams);
        }
    }
}
